Technical Field
Wind turbines or wind farms comprising a multiplicity of wind turbines have long been known in a wide variety of forms, embodiments, sizes and variants.
Description of the Related Art
A wind turbine is an installation which transforms energy which is available in the wind into electrical energy by conversion. This electrical energy is primarily fed into an electric grid.
The known disadvantage of wind energy consists in that it fluctuates with the wind, i.e., the electrical energy generated by the wind turbine can fluctuate depending on the present wind speed. However, this strictly speaking only applies in the partial-load range, i.e., in the range of the wind turbine between a first wind speed (starting wind) and a second wind speed (nominal wind). That is to say that if the wind strength is greater than the nominal wind speed, fluctuations in the wind speed which are above the nominal wind speed do not result in any fluctuations in the generation of the electrical energy because the wind turbine is controlled, for example by setting the rotor blades of the wind turbine, in such a way that the rotation speed and/or the electric power generated remains virtually constant.
However, if a wind turbine is in the partial-load range for the majority of its operation and in this partial-load range the generated electric power of the wind turbine also fluctuates directly with the wind speed, fluctuating power, i.e., a fluctuating absolute value of the electric power (namely the active power), is also constantly fed into the grid with fluctuating wind speed.
Thus, wind turbines fail in terms of many considerations with respect to grid management as generators for a base load because it is not possible to predict with sufficient probability the power input of the wind turbine to the grid.
It would indeed now be theoretically possible to run a wind turbine suboptimally, for example not running the wind turbine at the maximum power in the partial-load range, but to operate it with a suboptimal power output such that, in the event of fluctuations in wind speed in the partial-load range, the rotor blades of the wind turbine are actuated in such a way that the fluctuation in the wind speed is compensated for and thus the wind turbine feeds a virtually constant power input into the grid.
The disadvantage of such a solution consists, however, in that even in the partial-load range of the wind turbine, the wind energy output of the wind turbine then consistently needs to be readjusted, for example by pitching the rotor blades or by actuating a suitable generator countertorque or a corresponding other measure, which firstly additionally costs energy for the operation of a wind turbine and secondly also continuously uses the corresponding component parts such that ageing and wear of said component parts is accelerated.
However, primarily valuable inputs of power are lost in the case of such an operating procedure and thus the entire wind turbine will only have a relatively low level of efficiency.
The German Patent and Trademark Office has searched the following prior art in the priority application with respect to the present application: DE 27 51 341 A1, GB 2 263 734 A, DE 197 16 645 A1 and US 2004/0267466 A1. Finally, reference is also made to EP 1 739 824 A2 and WO 2010/048706 A1 as further prior art. EP 1 739 824 proposes (see FIG. 6 therein) that for the case where, in the partial-load operating mode, the wind farm power increases, the power of the wind farm which is fed into the grid does not increase as much as the wind farm power, but the increase in the power fed into the grid is made more uniform by the controlled use of an electrolysis device.